Digital fabrication is changing how houses are designed, engineered and built.
Bruce Bell, managing director of Facit Homes, one of the pioneers of the approach, is adamant that it is the future.
“We get what we want! Not what the builder thinks will work and make his life easier,” he said.
Digital fabrication has allowed the architects to create their own timber frame system and have more control on the final quality and speed of construction of a project. The timber frame, which they call a chassis - like the chassis of a car - has all of the service channels integrated and pre-planned, reducing first fix time.
“There is no onsite bodging or cutting holes or notches,” explained Bell. “Taking cues from the manufacturing industry we use Design for Assembly techniques which ensures that our build components are assembled in the most efficient manner possible.”
Like many architects, Facit Homes use a Building Information Model (BIM) to control the design and construction process but they have taken it a step further by using the 3D geometry of their individual building components to control a CNC machine to output exact physical replicas.
CNC stands for computer numerical control. A computer converts the design into numbers. The numbers can be considered to be the coordinates of a graph, and they control the movement of a cutter along the X, Y and Z axes, allowing plywood to be machined in three directions (3D manufacture). These pieces are then assembled into lightweight blocks that click together like Lego bricks.
“Every physical component is 100 per cent accurate to the 3D model which has been tested and resolved,” said Bell. “By combining this technology with BIM, we are able to quantify materials and costs much more accurately. We refer to this digital manufacturing as the D-Process.”
“Our architects can directly influence the way the design and manufacturing of our components is conceived because we fuse the disciplines of architect and maker.
“For clients, this means one point of contact through the planning, manufacturing, assembly and fit out stages.”
The approach scores points on almost every aspect of building. It is dramatically quicker to assemble; a four-bedroom house can be assembled in under a week. It needs fewer materials, meaning it is substantially more ecological. It requires a smaller work force, meaning it is considerably more efficient.
It is also fundamentally about creating unique, custom-made homes, and not merely ‘cookie-cutter’ houses.
Bell was motivated to go down this route frustrated by the traditional method of house building, which he describes as “messy, chaotic and horrible.”
“You are doing these drawings on computer down to the millimetre and then you are handing them over to somebody who gets out the tape measure and chops up a bit of wood,” he said.
The potential for the process also goes far beyond the central chassis. Bespoke staircases, kitchens and other joinery packages can all be created fusing technology with craftsmanship.
So what does this mean for the traditional roles of architect, engineer and builder?
Bell believes they have created a new business model for themselves as architects.
“We are no longer only being paid fees for design services but we have additional revenue streams as a manufacturer and a main contractor,” he said. “Our architects are absorbed much more into the reality of building which informs future projects. We are constantly in R&D.”
Historically, Bell says architects were much closer to the craft, but as legislation increased, it forced disciplines and specialisms apart. Technology, he believes, is now bring them closer together again.
“We see this as being a good thing, informing a more well-rounded group of professionals,” he said.
Bell is keen to point out that the use of technology is not at the expense of personality injected into the finished home.
“We utilise a hybrid approach in the manufacturing of our structure," he said. "We use technology but finish it still using traditional skills. The world will always need skilled craftsman.”
It does come at a cost, however, with the cost per square metre of a home ranging between $3,500 and $4,500. However, Bell says this is offset by the efficiencies created. Indeed, he believes that the homes actually come in at 15 per cent cheaper than what it would cost using traditional methods as much less time is spent on site.
The digital fabrication revolution has truly begun.